Junction-box for sparking plugs.



J. DUBAIL. JUNCTION BOX FOR SPARKING PLUGS.

APPLICATION FILED JUNE 1,1910.

Patented Mar. '7, 1911.

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JULEs DUBAIL, or DELLE, FRANCE, Assmnon TO socrn'rn mnUs'rRiEL E DEBELLE,

. or DELLE, FRANCE.

JUNCTION-BOX FOR SPARKING PLUGS.

To all whom it may concern:

Be it known that T, Jones DUBAIL, citizen of the Republic of France,residing atDelle, Territoire de Belfort, France, have invented new anduseful Improvements in Junction- Boxes for Sparking Plugs, of which thefollowing is a specification. I It. is interesting, particularly inmotors with several cylinders, that it is possible to separate from thesource of electricity the ignition device of any oneof the cylinderswithout stopping the motor-(To this end ignition devices have beenconstructed terminating in a contact plug, to which the leads for theignition current are joined.

The arrangement which forms the object of the present invention offersover exist ing systems the advantage of simplicity both as regards theconstruction and the connection of the current supplyconductor.

One form of a. construction of this device is represented in section andin plan respectively in Figures 1 and 2 of the ac-' companying drawing.Fig. 3 illustrates in section a second constructional form thereof, andFig. 4 represents still another constructional form of the device.

A washer-like member or washer g of insulating material is provided withtwo recesses f, f, and-with an opening slightly larger than the diameterof a stem or screw 6 passing through it and beingby preference ofatubular form. This screw, which has a central passage 2'- extendingthrough its whole length, is provided with a conical head, slotted fortightening purposes and capable of entering one of the recesses f in thewasher g. A nut e which is likewise conical and by preference hexagonal,for the purpose of preventing it from turning during tightening, isadapted to enter the recess f in the washerg, which latter recess is atc likewise of hexagonal shape for the reception of the nut.

The washer g is provided with a lateral opening j for the introductionof the conductor m attached to the source of electricity. As thisconductor is always composed of several individual wires, it is easy,after its introduction into the opening j, to lead one half m of itswires to the recess f and the other half an to the recess f, and

V to so spread them at these points as to pre- 'vent the formation ofexcessively thick ends .and to enable the -.tightening of the nut eSpecification of Letters Patent. Patented Egan 7, 1911 Application'filedJune 1, 1910.. Serial No. 564,424.

on the screw 1) which can still be accompllshed in spite of thewires,because of the free play provided for it in the central opemng ofthe washer g. In this manner the conductors are held firmly in a perfectmanner in the recesses f f, and between the screw 5 and its nut e.

The screw 1) may be prolonged at a in the form of a tubular end which issplitand contracted or reduced so as. to fitwithout play onto the plugcontact at the extremity of the ignition device. i

Fig. 3' represents a modified construction in which the screw 6 insteadof extending beyond "'the nut e is provided with slots n mllled betweenthe head and nut and permitting attachment to the plug contact ofthelatter may be rendered elastic and easily bent, either peripherallycontracted or enlarged, to facilitate engagement of the screw 7) withthe plug contact of the ignition evice- (not shown). Finally in thecasewhere, by the nature of the insulating material chosen for thewasher g, the pressure exerted by the screw bagainst the Hut 6 would be.liable to cause breakage of the insulating washer, the recesses f, f(Fig. 1) could be replaced by cylindrical cavities h, h (Fig. 3)embedded in which are metal rings d,.d' of triangular section whentheheads of the screw and nut are conical, or of rectan ular section ifthe screw and nut have cylin rical heads, said rings being adapted totake up the radialor longitudinal strain due to the tightening of thescrew b against the nut 0.

According to the construction shown in Fig. 4, the device comprises abody 9 of insulating material provided with a lateral opening j for theintroduction of the leading-in conductor m attached to the electricsource. The screw I) having a conical head is provided with an axialopening 2', and with a tubular end which is split and reduced so as tobe capable of being attached I :the device.

contained within the insulating member as shown in the drawing. Theadvantage of this modification is that the leading-in device iscompletely surrounded by the insulating-washer 9 thereby protecting theoperator against any shocks which might resultfrom his touching theconductive parts of Moreover in this construction a rein'forcingmetallic washer or insertion (Z is used for the attachment of theconductor clamped beneath the head of the screw, and which is likewiseembedded in the insulati body g, whereby the construction is consi'e'rably simplified. 1

What I desire-to protect and claim by Letters Patent is t "1.; In adevice of the character described,

"the combination with a washer likememberofinsulating material havingatransverse openingtherethrough and recesses adjacent said'openingpresenting inclined faces, there being a radial opening in said member,'of

'J'a tnbular conducting member insertible in the" transverse i openingand bein of less diameter than the latter, saidtubu ar member lbeingslotted and adapted totelescope with a correspondingly formed plug aheadcarried by said conducting member and being infclined-toconform to theinclined faces 3o of the recesses, and =means whereby. said head maybewedgedintooneof said re cessed and clamp conducting wires in. thedevice.- v

2. In a device of the character described, the combination with a.washer like member of insulating material havinga transverse openingtherethroughand recesses, immediately adjacent said opening presentingin- 'clined faces, there being a radial substantially conical opening'insaid member, of a hollow conducting screw insertible in the transverseopening and being of less diameter than the transverse-opening, saidscrew being slotted and adapted to telescopically I engage acorrespondingly formed plug, and said screw havinga head thesurface of Pwhich is inclinedto conform to the inclined face of a recess adjacentthe transverse opening, and a nut adaptedto engage one end of saidscrew, said nut having an inclined sur-' ,JULES DUBAIL.

